Process for separating borax and potassium chlorid.



' To all'whom it may concern:

JOHN w.

I ments in Processes HOBNSEY;

PBOCESS IEQR SEPARATING BORA X AND POTASSIUM CHLORIIL:

No Drawing. Application filed April 17,

Be it known that 1, JOHN W. HoRNsEr, a citizen of the United States, and a resident of Summit, Union county, New Jersey, have invented certain new and useful Improvefor Separating Borax and Potassium Chlorid in Mixtures of the Same, of which he following is a specification. I

My invention relates to theseparation of borax and potassium salts from mixtures of salts containing these compounds.

- at a temperature of, approximately 200 F.

are present in certain be present in very much Whenthe mixtures are not in solution l first dissolve them, and I have found that it is possibleto separate from a brine containing, a variety of salts, such, for instance, as exist in certain alkali lakes and other waters, a mixture of potassium chlorid (KCl) and borax (sodium tetra borate, Na B,O, 10H O). These salts, in dissolving and recrystallizing, normally precipitate or crystallize out together. The object of my in vention to separate these salts so that they maybe ecovered in a state of marketable purity.

It is well known that if these two proportions in a solution,* either with or without minor percentages of other salts,a cooling of this solution will cause the precipitation of a salt cake containing both borax and potassium chlorid, but that if either one of these two salts greater quantity than the other, the precipitate will consist substantially of the salt which largely predominates.

I have found, however, that if the relative percentages of these salts is suchthat they would tend normally to crystallize outtogether from asaturated or nearly saturated solution, a very different result may be obtained from a more or less dilute'solution. With this object in view, I take a solution containing a-mixture of potassium chlorid and borax whichis saturated, or nearly so,

I first dilute the solution with water at approximately the same temperature until a cific gravity.

fairly dilute solution results; or

in first makm up the solution, enough watermay be used to give approximately the desired spe- I find that a solution of the specific gravity of 1.12 to 1.22 at atemperature of 200 F. answers very well for this purpose. I then cool this diluted brine to a earners .a

0F sumar'r, NEW JERSEY, ans Am) EY-rEonuc'rs COMPANY, a coaronnrron or DELAWARE.

1915. Seria1No.22,105.

cleansing operation.

as limiting myself to salts.

alternate crops of borax and chlorid, repeating ton.

ASSIGNOB IQ GENERAL BEDUC'LIN I Patented Dec'.24l, 1191s.

temperature of preferably about 40 F., at which temperature part of the borax is precipitated, and when separated from the solution is of a sufiicient degree of purity to be marketable after the usual washing-or I then evaporate a suflicient amount of water from the filtrate remaining-after the separation of the borax, which filtrate is saturated at its temperature to bring it substantially tothe point of saturation at a higher temperature, that is, to the point at which crystals begin to v ture which may be usedfor evaporation. then cool the saturated solution from its elevated temperature to preferably about 40 F., at which temperature potassium chlorid is precip'tated from the solution, which, after the usual washing or cleansing operation, is of a marketable. degree of urity.

I do not, however, wish to beunderstood the particular temperatures or specific-gravity specified above, as these may be varied in comparatively wide ranges. The remaining filtrate is still saturated at the temperature. at

both potassium chloridand borax. I therefore pass the filtrate through thesame cycle, heating, diluting and cooling,- then concentrating and cooling to the same and density. specified above, thus obtain ng potassium this operation untilthe separation is substantially completed, orI may mix the filtrate with new material an repeat the same cycles of operation indefinitely, with the resultingalternate crops of borax and potassium 'chlorid. If appreciable percentages of other salts, however, are present in the solution it is preferable to mix the filtrate, after the potassium chlorid has been separated, with new material, until the percentage of other salts becomes so high as to render it advisable to remove at least a portion of such salts by evaporation or otherwise. I

In this manner I am enabled-to resolve mixtures of potassium chlorid and borax into their component salts.

The terms and expressions which I have which the potassium' 'chlorid has been precipitated, and contains form at the temperatemperature I employed are usedas terms of description and not of limitation, and I have no inten' sions, of excluding any step which may be 'ing such any of the features which have described, but recognize that various modifications are possible within the scope of the invention claimed.

Having described my process forefieCtseparation, what I desire to claim any equivalent of 1. The method of separating borax and potassium chlorid, which consists in cooling a heated solution containingsaid salts,hav-

mg a specific gravity of from 1.12 to 1.22 at about 200 F., thereby precipitating borax and separating the borax from the solution. 2. A method of separating potassium v chlorid and borax from a mixture of salts in 1.22 at about 200 tate borax, separating the borax from the so- I concentrating and cooling same to .tate potassium chlorid,

solution, which, consists in bringing the solution to a specific gravity offrom 1.12 to F., and cooling to precipilution, and. then concentrating the liquid residue and cooling same to precipitate p0 tassiumchlorid. Y

3. The method of separating boraxand potassium chlorid from a mixture of salts in solution which consists in diluting the solution to a specific gravity of from 1.12 to 1.22 at about 200 F., cooling and precipitating the borax, separating the precipitate from the solution, heating the liquid residue,.

' precipi and repeatlng the cycle of operations with the,residue of the said mixture i n y 4. The methodof separating borax from potassium chlorid, which consists in cooling a dilute solution of borax and potassium. chlorid havmg a specific gravity of from- F., thus precipiseparating. it therefrom, v cooling the filtrate, thus precipitating potassium chlorid and separatlng therefrom, borax and potassium chlorid, and repeating the cycle. x 5. The method of separating borax and potassium chlorid which consists in cooling a heated solution of said salts having a specific gravity of about-.116 at about 200 F., and separating the precipitate.

v6. The method of potassium chlorid which consists in cooling a heated solution of said salts having a specific gravity of about 1.16 at about 200 F separating a precipitate, then concen trating by evaporation and cooling the solution, and separating a further precipitate.

The process of obtaining potassium chlorid from a solution containing borax and potassium chlorid inga heated dilute solution having a specific gravity of from 1.12 to 1.22 at about 200 F., separating borax as a precipitate by cooling, then concentrating and cooling the solution, and separating potassium chlorid as a precipitate.

8. The chlorid from a solution of borax and potassium chlorid, which consists in diluting the solution to 1.12 to 1.22 at about 200 F., cooling to about 40 F. to precipitate the borax, separating the borax from the solution, concentrating the resulting solution at about 200 F., cooling toabout 40 F. to precipitate the potassium chlorid. v

JOHN W. HORN SEY.

adding a further mixture of.

a specific gravity of from separating borax and v which consists in tak- 

